After having many girls in every port of the world, womanizing sailor Sonny Phyffe (Dennis O'Keefe) finally meets his match with spunky Janie Prescott (Martha Scott) and the duo are promptly married. Sonny's father, retired Colonel and con-man Hector Phyffe (Adolphe Menjou) surfaces for the wedding with many new crooked schemes up his sleeve. Compounding the tension is the fact that the Colonel is the kept husband of high-strung Wagnerian opera star Genya Smelana (Pola Negri), who believes Hector to be much younger than he actually is ...and childless. Adding to the commotion is Janie's neurotic, financially-ruined mother Mrs. Prescott (Billie Burke), who is now seeking a new fortune. Sonny and Janie are all set for their honeymoon getaway when the Colonel plunges them into a comical misadventure.Opening and closing with beautifully, wacky animated graphics and climaxing in a nutty, full cast sing-a-long to Wagner's Tannhauser, Hi Diddle Diddle is totally unfettered 40s screwball comedy performedwith great gusto by an all-star cast.